Tenderizing casings



1952 F. L, KAUFFMAN ET AL 2,608,487

TENDERIZING CASING 4 Sheets-Sheet 1 Filed April 20, 1950 Fly. 1

INVENTQRS 1952 F. L. KAUFFMAN ET AL 2,608,487

TENDERIZING CASING BY m 12;;

ATTORNEY Aug. 1952 F. KAUFFMAN ET AL 2,608,487

TENDERIZING CASING 4 Sheets-Sheet 5 Filed April; 20, 1950 INVENTORS Hog a Z [ldvf/man and Walter/ll. Urbain ATTORNEY 26, 19 F. L. KAUFFMAN ET AL 2,608,487

TENDERIZING CASING Filed April 20, 1950 4 Sheets-Sheet 4 -20 E i! a q E -15 m 5 f r 40 V a j .11 Q. S 5 u EFFECT or EXPOSUZE T0 71/: 360 WATT awn/2c o A7 5 INCHES UPON b9 (AS/N6 TENDER/V585 ACTUAL TIME OF EXPOSURE IN MINUTES 0 o UNSMOKED CHANGE IN PENETROME 75g RE D/H68 A o 1 2 3 4 5 e 2' a e no u l2 flqyJL/izz/fman ATUAL TIME 0F Exposuae \N Mmu1Es and Walter! U fi j' INVENTORS ATTORNEY Patented Aug. 26, 1952 TENDERIZING CASINGS Floyd L. Kaufiman, Palos Park, and Walter M. Urbain, Western Springs, 11]., assignors to Swift & Company, Chicago, Ill., a corporation of Illinois Application April 20, 1950, Serial No. 157,140

V 1 The present invention relates to a novel method and apparatus for effecting tenderization of natural casings. More specifically, the invention relates to a novel method and apparatus for effecting the tenderization of natural casings, either stuffed'or prior to stuffing, by treatment with facture of frankfurters and other sausages similar in size, are not normally acceptable for such purpose because of their natural toughness, which renders them difiicult to masticate and digest.

The present invention contemplates the treatment of natural casings prepared from edible animal intestines with ultraviolet radiation, with an appreciable portion of the radiation having a wave length falling in the range of about 1800 to 2500 angstrom units. It has been found from actual tests that normally tough hog casings, for example, can be tenderized very quickly and economically by exposing all portions of the same directly and preferably at short range to the action of an ultraviolet radiator for a period of time,depending onthe output of the radiator and the particular distance. It has also been found that stufi-ed natural casings such as, hog casings,

for example, can be tenderized by a similar treatment prior to smoking. It has further been found that ultraviolet light improves the tenderness properties of sausages, such as frankfurters, after they have been smoked, usually requiringconsiderably. more ultraviolet energy for tenderizing than for similar unsmoked sausages.

7 Claims. (Cl. 99-475) Natural casings have been tenderized heretofore by, the use of certain enzyme solutions, as disclosed in the patent to Ramsbottom et "al.,-

tion is to impart such properties to a normallytough natural casing as will render the same easy to masticate-and digest.

An important object of the invention is to pro-1' vide a method and apparatus whereby normally tough animal casings may be quickly tenderized 2 to a desired substantial degree without materia disintegration. 1

Another important object of the invention is to provide a quick and economicalmethod oi tenderizing natural casings and which method does not require the application of any treating solutions or any special temperature or humidification conditionsof the atmosphere'within the treatingchamber. a l

A more specific object of the invention is to provide a method whereby normally tough casings, such as hog casings, beef, and Indian-sheep casings, may be tenderized and thus rendered useful in the manufacture of high grade frankfurters and other sausage products requiring a tender casing.

Other objects and advantages of the invention will be apparent from the following description taken in conjunction with the accompanying drawing, in which:

Figure l diagrammatically illustrates a simple typeof apparatus that may be employed for tenderizing unstuifed, natural casings;

Figure 2 is an enlarged sectional view taken on the line 2-2 of Figure 1;

Figure 3 diagrammatically illustrates an apparatus similar to that of Figure 1, except that it is modified so that it may be employed for tenderizing stufied, natural casings;

Figure 4 is a plan view of one form of apparatus for practicing the processof the invention in a continuous manner;

Figure 5 is a side view partly in section of the apparatus shown in Figure 4; l

Figure 6 is a vertical section along the lines 6--6 of Figure 5;

Figure 7 is a view of an ideal arrangement of lights for producing maximum theoretical exposure of the product l Figure 8 is a plan view of a modified type of apparatus adapted for treating sausages arranged on smoking sticks;

Figure9 is a side view of the tenderizing conveyor shown in Figure 8;

Figure 10 is a vertical section taken along the line I 0-4 0 of Figure 8; V

Figure 11 is a graph showingthe per cent change in tenderness of casings as measured by a penetrometer plotted against the time of exposure to ultraviolet light; and

Figure 12 is another graph similar to the graph including an elongated tube 2 and a reflector 3."

Such light source may be a 360 watt Uviarc ultra violet lamp, for example. A stick 4 of wood or 1 other suitable material is provided with a hook 5 secured to one end thereof. adapted to cooperate with a hook .6 which may numeral The book 51 is be fastened to one end' of a driven shaft 1. A pulley 8 may be mounted upon the shaft 7' and driven by a belt 9. A suitable length of unstuffed natural casing I is threaded onto the rod 4 and then the rod 4 is hung by the hook 5 from the hook 6 in substantial parallelism with and about 5 inches from the ultraviolet light tube '2, as indicated in Figure 2. The shaft 1 is adapted to be slowly rotated at about -120 P. M. bythe belt 9, and pulley 8 by any conventional or suitable means (not shown).

Preparatory to tenderization, the casings are right anglesto' the casing which was likewise I fitted over a glass rod. During treatment with the lights, the casings were rotated slowly by mechanical means. The time of exposure as listed below is the total time the casing was exposed to the light. As only about one-third of the casing was exposed at one instant, the

washed and rinsed to effect to removal ofsalt,

etc.,'and a suitable length. is then threaded onto therod' 4,. which is then hung. from the hook 6:

and slowly rotated in the manner. described in order to expose the casings while in a moist. condition to ultraviolet light. having a wave length specified therein. When a single ultraviolet lighttube 2gis' used,.only about one third of the exterior surface ofv the casing, .Ill is exposedto the direct rays of the. ultraviolet light at: any given instant; hence, the actual time that a pare ticular section of the casing I0 is exposed to the direct rays of the ultraviolet lightis approximatelyone-third of the total time that said casing is rotated. ,In this manner, longitudinal portions of thecasing lil are progressively exposedito the rays-oftheultraviolet light emanating from the While some slight heating may result,

tube 2. this has anegligible' efiect on the tenderization 0f; the, casings as well be evident from Table 1.

Moreover, the'exposed portions are continuously cooled by the surrounding; air of the treating room beforebeing again exposed to the light rays on the next-revolution-of the shaft 7. Thus, portions of the casing ID are intermittently exposedto the action of theultraviolet light rays. The degree of tenderization can be varied by altering the time interval: of exposure, as: will appearmorefully hereinafter;

The actual amount of tenderization ofthe easing [0 effected by the treatment with theultraviolet light may be determined bythe use ofa penetrometer'which measures the force necessary to puncture a stufied casing-with a--st,eel ball. The-penetrometer constitutes no part of the-present invention, but asa-matterof information,.

it comprises a steel ball having a diameter'of a" inch mounted upon a rod of smaller diameter operatively attachedto a suitable. gauge; The

penetrometer gauge is arbitrarily calibrated" so that one unit corresponds to one-twentieth of a pound, the. entire gauge scale including graduationsirom 1.130 200.- resentative readings, an average 0f= anumberof readings to is :used for each test. In all cases, the experimental control, orcomparison testspecimen, consists of an untreated portion of a casing, the remainderof whichis treated to.ascertain thetenderizing-efiected by agiven exposure to ultraviolet light.

The following'tabulation, identified as-Table I, shows average penetrometer' readingsfor: un-- stuffed hog casings: exposed to various light light sources such as a '360watt Uviarc ultraviolet lamp (with and without a 970 Core filter) and a 260 vwatt infra-red lamp. In each instanceyth'e casing was positioned 1 approximatelyi 5' inches from the lamp. In making, the ultravioletli'gh't treatments,. the: casings were" stretchedl over: a f small glass rod and hung. parallel to the tube of I an ultraviolet lampriequipped: with at reflector.v The infra-red treatmentwas made by stationin the infra-red lamp: equipped with-a reflector at In order to obtain I rep-- actual time the particular section was exposed to the light was approximately one-third of the In addition to indicating the various: types o'f ultra-violet, etc. lamps en1ployed,- Table I" in-- dicates the timed exposure inminutes in-1'otating test specimens, the toughnessof the control specimen as determined by thepenetrometer,'= the toughness of the treated casing after ex posure; the diiference'betWeen the penetrometer readings of thecasing material-before and after exposure and the average difference in tough-'- ness of the 'several casings tested; The data show that-substantial-tenderization o'c'cur's as a -result of the treatment' with the ultraviolet light. The data for the treatment with the filtered light of the Uviarc= lamp show n0 tender-i'z'atio'n,- the wave length of this filtered lig-h-tbeiflgsub stantiallyentirely above 2800- angstrom-- u'n' itse Treatment withthe-- infra're'd lampindicates that tenderi'zation is not dueto heat" as shownby the fact that no appreciable loweringofthe penetrometer readings was observed after the casings were e'xpo'sed to the heat-rays of said lamp.

In- Table II, the relationship between -the de'-" gree'- of treatment as expressed-in" time or total 1 energy and the amount-, or tenderizing is showrii- Thedata were obtained by exposing hogcasings in-a manner similar to that described for thetreatment shown in Table IL Also, thesanipl'es' wererotated as'before; the-data g iven for the time of exposure and the total-energy manure- Watts-p'er square centimeter represent the actual treatment of" thecasings: at any given points They are calculat'ed as one thii'd of the to'tal time-of expo'sure and are one-third of the f total microwatts emitted during: the: entiretime of The data tabulated in Table II is shown graphically in Figure 11 wherein the .timeof ex:- posure is plotted against the per cent change in penetrometer readings. It will be observed from the curve. that the tenderizing efiect reaches, a

. maximum at a time of exposure of about 5 minutes, which representsa total energy of 1,432,000 microwatts per square centimeter.

After about 6 minutes exposure there, is a definite toughening of the casing as shown in Figure 11. In other words, the tenderizing effect reaches a maximum at. around about 4 minutes to 6 minutes andthereafter there is ,a .fallingofii oi the tenderizing efieict. The: decrease in the tenderizing efiect may be. due to dehydrationv of the casing since such dehydration can be observed from the dry appearance of the casing.

In calculating the total energy listed above, use was made of published data on the ultraviolet light source. The radiator was used according to the directions of the manufacturer so that the energy output and the spectral distribution of the energy output could be expected to be identical with. the measurementsmade by the manufacturer. The reflectors supplied with the lamps were used. In determining the energy falling on a square centimeter of surface two additional quantities were needed. These were the time for which the lamp was operated and the distance between the object and radiator.

,square law. Other factors being constant, this law applies and may be stated as follows:

where E1 and E2 are the energies and D2 and D1 are the distances between the object and radiator. In this law the assumption is made that the radiator is a point radiator. The. ultraviolet sources used here have physical dimensions and are not points; consequently, the law stated above applies only approximately and deviations from it becomes greater as the distance between the object and radiator becomes smaller.

The method of calculation may be illustrated by the following example. The'energy given off by a 360 watt Uviarc lamp between 1800 and 2500 angstroms is 77 microwatts per second per square centimeter at one meter when operating according;

to the directions of the manufacturer. If this lamp were used at a distance of 5 inches or 0.127 meter for one minute the total energy falling on a square centimeter would be calculated as follows:

E5 equal 4,770 microwatts per second persquare centimeter or in 60 seconds 280,000 microwatts per 1 square centimeter.

The exact theory or explanation of the phe- 6 strom units produced no improved tenderlzatlon of the casings. The lamp without a filter emits wave lengthsas low as 1800 angstrom units and definitely does produce tenderization. Also, when casings are subjected to radiation from an ultras violet sterilization lamp, such as used in quickaging meat, which emits practically no radiation having a wave length below 2500,angstroms- (see James Patents 2,169,081 and 2,192,348), the,

casings are not tenderized even after prolonged exposure to the radiation from suchan ultraviolet sterilization lamp. Therefore, the active wave length which is efiective for tenderizing casings in accordance with the herein disclosed process is in the range of between about 1800 and 2500 angstrom units.

Figure 3' illustrates the manner in which stuffed casings may be tenderized by exposure to ultraviolet light. As illustrated, a stuffed casing Ill prior to linking and smoking, is suspended from the'h'ook B'in substantial parallelism with the ultraviolet light tube 2 and is slowly rotated with the shaft I.

In TableIII are shown data obtained by treat-- ing stuffed hog casings with radiation from a 1200 watt Uviarc ultraviolet lamp. The sausages were located 5 inches distant from the radiator and were slowly rotated. The time of exposure and the penetrometer readings were determined as described heretofore in connection with Table II. In both the control and the irradiated samples the sausages were completely processed prior to makingthe penetrometer readings. The processing comprised cooking and smoking so that a finished product was obtained according to'commercial practice.

TABLE III Efiect of exposure to the 1200 watt Uviarc at 5 inches upon unsmoked frankfurters Penetrometer Readings [1f. ctual Micro- 1me o watts per B efore After Per- Avera e Expqsme 1' Expo Expo- 1 Diff. cent Perce t sure sure Difi. Difl.

95.9 56. 0 39. 9 41. 6 99.3 61.1 r 36.2 35.5 99. 3 62. 6 1 36. 7 37. 0. 20 Sec..." 740, 000 99.5 65. 7 33. 8 34. 0 37. 6 1 120: O '74. 6 45. 4 37. 8

V 99.7 63.7 35.9 36.1 I 114. 7 70. l 44. 6 38. 1 1 105. 5 70. 7 34. 8 33. 0 V 96. 1 60. 1 36. 0 37. 5 30 sec... 1, 110, 000 95. 9 59. 2 36. 7 1 37. 2 41. 7

120. 0" 59. 2 60. 8 50. 5 V 96. i 65. 4 31. 0 32. 2 .1 it. a: as a; 1 96. 1 50.7, 45.0 .412

92. 4 57. 5 34. 9 37. 8 60 seen.-. 2, 220, 000 105. 4 56. 0 49. 5 47. 0 46. 6

j 119.5 53. 7 65.8 55.0 92. 4 54. 5 37. 9 41. 0 860--.). 1 2, 960, 000 105. 5 51. 5 54. 0 51 .2 i 48; 6 119.5 55.4 64.1 53.6 a '1, 2 min-.. 4,440, 000 3 3 fig 23:2 51. 4 4111111"... 8,880,000 ere 32.2 64.8 66.8 66.8 8 nmn... 17, 760,000 I 97.0 31. 4 65. 6 67.6 67. 6

, The ,data in Table III is shown also in the form of a curve, in Figure 12. It will be observed that the tenderizing efiect reaches a maximum at around 5 minutes and a total energy of 11,100,000

9 the sausages is then placed on the hooks l8 of a continuous conveyor 20. The conveyor is mounted on shafts 2| and 22 and is adapted to convey the sausages through an ultraviolet light chamber 24 wherein the sausages are exposed to ultraviolet light radiating from lamps 25. The

' lamps are preferably arranged in circular form around the conveyor as shown in Figure 6 so that the lamps are substantially equidistant in all directions fromthe sausages and the rays strike the sausages on all sides.

An ideal arrangement which is desired to be approached as nearly as possible is shown in Figure 7. A near approach to this ideal arrangement may be obtained by laying the frankfurters lengthwise on the conveyor instead of hanging them on smoking sticks from the hooks. A modification in which the frankfurters are laid lengthwise on the conveyoris shown at the top of Figure 7. In this way the frankfurters pass in a substantially horizontal straight line between the lamps and the ideal condition as to equidistance on all sides from the lamps, and complete exposure of the entire surface of the frankfurters to the light rays is more nearly approached. Since I Cir the degree of tenderization is dependent upon the total energy of the ultraviolet rays striking the surface of the sausages, it is important that uniform exposure of the casings be obtained. It is intended that the lights be arranged in such positions andat such distances from the sausages that rays of substantially equal intensity strike the entire surface of the sausage casings at the same time. The arrangements of sausages during exposure to the ultraviolet rays are merely illustrative, and other means and methods of exposing the casings to accomplish the desired results may be used.

After the ultraviolet light treatment the sausages may be removed from the conveyor by an operator and placed on a smoking tree 26 preparatory to placing the sausages in smokehouses. If the sausages have already been arranged on a smoking stick, as shown in Figure 5, all that is necessary for the operator to do is to remove the sausage sticks from the hooks on the conveyor and transfer them to the smoking tree. In case the sausages are conveyed in tandem between the lights, as shown in Figure 7, it may be necessary for the operator to remove the string of sausages from the conveyor and arrange them on the smoking sticks which are then placed on the smoking tree.

Figures 8, 9, and 10 show a modified form of apparatus wherein the smoking sticks loaded with the sausages are arranged crosswise of the conveyor instead of parallel to the conveyor. This modification has certain advantages in securing more uniform exposure of the surfaces of the sausages to the ultraviolet light. As shown in the drawings, two stufling and linking tables 3| and 32 may be provided for feeding the frankfurters to the ultraviolet light chamber 35. In this modification, the conveyor is made up of two parallel chains or belts 36 and 38. A series of sausage sticks 40 may be mounted crosswise of the conveyor chains. The sausages are carried by the conveyor past the ultraviolet lights 42, the speed of the conveyor being correlated with the length of the lights so that the proper time of exposure of the sausages to the ultraviolet rays is secured. It will be observed that the lights are arranged above and below the upper flights of the conveyor and the upper and lower group of lights are offset, as shown in Figure 10, so that substantially uniform exposure of the sausages results. The conveyor'is driven by a motor 43 which is connected by a drive chain 44 to drive shaft 45 of the conveyor. In this modification, the smoking sticks are removed from the conveyor after passing through the ultraviolet light chamber and may be placed on a smoking tree shown diagrammatically in Figure 8 and represented by the numeral 46. 1 i

In practicing the invention, the conditions under which the casings may be tenderized may vary considerably, depending upon the character of the productfthat is, whether it is an unstuffed, a stuffed, or a stufied and smoking casing. Certain general conditions, however, may be stated as permissible and preferred operating ranges. The distance of the radiator from the casing will not vary with the different products treated. It is desirable to bring the radiator as close to the product as possible without heating or burning so as to avoid dehydrating the casing. We contemplate using the lamp at a distance of about 1 inch to 5 inches and preferably at a distance of around 5 inches. In practice the distance would be governed by the physical size of the radiators, the number of radiators, and the space relationship between the casings and the radiator or radiators.

The time of treatment with the ultraviolet rays will depend somewhat on the capacity of the unit desired. In general, it may be said thatas short a time as possible is generally preferred. -We contemplate, for example, using a time ofabout 10 seconds to 30 seconds, although longer time periods, for example, up to several minutes, may be used. It will be appreciated that the time is related to the total energy which in turn depends on the size and number and the distance of the lamps from the object. The factors of time, distance, and the energy output determine the total energy. In general, however, we contemplate using total energies as indicated in Table VII, wherein operating and preferred ranges of total energy microwatts per square centimeter are given for unstufied,' stuffed, and stuffed and The casings useful in the present invention include freshly prepared casings and those which have been salted and stored under refrigeration for some time. The saltedcasings are washed prior to tenderizing to remoisten. The casings are treated in a moist condition but excess moisture is undesirable because of absorption. of light rays by the water.

It will be understood that various means may be used to support the unstufied or the stuflfed casings relative to the source of ultraviolet light, that the distance between the light source and the casings to be treated may be varied within reasonable limits from the distance specifically disclosed herein, and that various types Of ultraviolet light lamps of diiferent wattage from that disclosed herein as an operative example may be employed.

This is a continuationin-part of application Serial No. 542,458, filed June 28, 1944, now abandoned.

appended claims. 7 1

Obviously, many modifications and variations of the invention hereinbefore set forth'maybe We claim? 1. The method of quickly tenderizing natural casings, which. comprises: exposing allportions of the exterior surface of said casings While in amoist condition to the direct action of ultraviolet light of' about 360 to 4500' Wattage emitting radiation having a wave length in the range of 1800 to. 2500 A. U. for a period ofv about seconds to several minutes at a distanceof about one to fiveinches whereby the casings, are tenderized.

2. The method of quickly tenderizing natural casings, which comprises: exposing all portions of the exterior surface of said casings while in a. moist condition to the direct action of ultraviolet light having a wattage of about 360and an active wave length in the range of 1800 to 2500A. U. for a period of about 10 seconds to six minutes with said casings positioned about: one to five inches from the source of said ultraviolet light whereby the casings are tenderized. V

3. Themethod' of tenderizing natural casings, which comprises the steps of: subjecting all portions of the exterior of the said casings while in a moist condition at a distance of about five inches from a source of ultravoilet light having awattage of about 120.0 and an active wave lengthin the range of 1800' to 2500 A. U., and maintaining said exposurefor a period of about 10 to 30 seconds whereby the casings are ten- 7 derized;

4. The method of quickly tenderizing natural casings; which comprises: exposing all portions of the exterior of the said casings while in a moist condition to the action of an ultraviolet light source emitting Waves of a length in the rangeof 1300 to 2500 A. U. and maintaining the exposure of the said casing to the action of said ultraviolet light to apply about 100,000 to 30;000,- 4

000 microwatts of energy from the said light source per square centimeter of easing surface area within a period not substantially in excess .of about 6 minutes.

12 5. The method of treatingunstufifed; natural casings. to tenderize the same, which comprises: subjecting all portionsof the exterior of-the said natural. casings while in a moist. conditionto radiation. from an ultraviolet light souroehaving an; activewave length in the range of 1800.130

2500 A. U-.,' and: maintainingthe exposure of thesaid casings to the action.- of the saidv radiation to apply about100,000to 2,000,000 microwatts of energy f1 om-=.th e said light source; per square centimeter of easing surface-area; within-aperiod not substantially in excess of about 6; minutes.

6, The methodrof treating astuffed', unsmoked natural casing;v to-tenderize the same, which com prises': subjecting; the stuifed' casing; while ina moist condition to: exposure on all sides from. a sourcerof ultraviolet light, said source having an active wave lengthinthe range of 1800 to:- 2500 A. U., and maintaining saidexposure te apply about 100,000to 15,000,000 rnicrowatts'of energy a period notsubstantially in excess of aboutli minutes, whereby the casings; aretenderizedi V FLOYD L. KAUFFM-An WALTER. M. URBAIN;

REFERENGE-S CITED 4 Y The 'follow-ing references are of record in: the file oftliis patentr T UNITED STATES PATENTS Number Name Date 2;1'09;081: James Aug'.18',, 1939 2,354,049

Bensel Deon 5;.1944 

1. THE METHOD OF QUICKLY TENDERIZING NATURAL CASINGS, WHICH COMPRISES: EXPOSING ALL PORTIONS OF THE EXTERIOR SURFACE OF SAID CASINGS WHILE IN A MOIST CONDIDTION TO THE DIRECT ACTION OF ULTRAVIOLET LIGHT OF ABOUT 360 TO 4500 WATTAGE EMITTING RADIATION HAVING A WAVE LENGTH IN THE RANGE OF 1800 TO 2500 A. U. FOR A PERIOD OF ABOUT 10 SECONDS TO SEVERAL MINUTES AT A DISTANCE OF ABOUT ONE TO FIVE INCHES WHEREBY THE CASINGS ARE TENDERIZED. 